The present invention relates to control valve devices for automatic transmissions.
One of the conventionally proposed control valve devices for automatic transmissions is known in JP-A 62-288753. This reference shows a structure that a control valve assembly including a valve, etc. for producing a control pressure for automatic shifting is mounted to a transmission casing.
Specifically, a valve body of the control valve assembly is mounted to the transmission casing. An oil strainer is fixed to the control valve assembly. The transmission casing having the control valve assembly arranged therein and an oil pan are connected to each other through a gasket.
With the known control valve device, however, since the transmission casing has a face on which the valve body is fixed inside an outer peripheral face on which the oil pan is fixed, large spaces which allow hand insertion are needed between the valve body of the control valve assembly and the transmission casing to enable mounting and dismounting of the control valve assembly. This results in enlarged size of the transmission casing, and increased number of stages of the valve body due to decrease in a circuit area of the control valve device.
Mounting and dismounting of the control valve assembly can be carried out by holding the oil strainer mounted to the valve body or a pipe. In this case, it is possible to deform the oil strainer to cause air suction, or to disengage the pipe to cause oil leakage.
It is, therefore, an object of the present invention to provide control valve devices for automatic transmissions, which enable easy mounting and dismounting of the control valve assembly even if the spaces are small between the valve body and the transmission casing.